Multiple outlet nozzle



P. G. MacGRx-:GOR 2544,55@

MULTIPLE OUTLET NOZZLE March 6, 1951 Original Filed Aug. 2, 1940 l l l l l l I l l l Patented Mar. 6, 1951 OFFICE MULTIPLE OUTLETlNOZZLE :il "This f-applicationis fa 'division .oflmy 4appl-ica- ="tion Serial No.3492916f1edfrlugustaz, 1594Uynow This inventionv rlatesto :ani improved @form .of nozzle for use in apparatus for extinguishingfiires i in-l aircraft, andy more'f particularly inf-and iaround o v`lthe motors ofa-irplanes.

Adiflicult land unique prohleminilthevartfof yextingu-isliing1lires isfpresented by res :that oc- #curi from l' time "to @time inf'airplan'esWhilefthe'airplanes are in -the'f-air. The forward:motion fa "plane *through the 'ai-r ttogether with 1the air 'stream produced 'iby 'fthe fpropeller or propellers Y f-creates "a very `frapidly moving stream fof fair vthrough-fand;arcundfthe motor ofa plane,y especiallywhen air cooled' internal combustion motors are-employed. -When'are breaks outin'v-such a motor,-thi`s high velocity-air stream, which may be movingatf-a rate'of -IUO-'milesfan houror more i relative to the plane, furthers the combustion of thel burning Amaterial by'therapid supply-'61?A oxy- -1gen'-to-it. A re in ani'airplane'v motor, .infact, "produces afcondition'quite-similar to thatexist- `ing in--a blowtorch causing extremely "rapi'dand high temperature combustion.

Such res -arelsometimes'causedby breaks in -o'il-or gasoline ffeed'- linesfbut are morefrequently caused'by oil and/or tgasoline escaping from a crackedfcylinder in' the motor. Are ofthis-type iis intensely hot #and rapidly damages .other vparts Y"of theplane,-makingitfextremely difficult 4and Asometimes impossible to 'landfthe plane with any f'degreeof='seeurity. Furthermore, if the Aplaneis not landed properly with such'a're burning, "the iire may spread very rapidly, :evenfcausing an explosion -*of lthe 'gasoline carried "by lthe plane. The hazard'therefore isVery-lgreatand-thefprobflem '-o'f extinguishing Y-such fa iire --While a "plane fk.exti-ngi-lis'hing devices.

Arprimary ioloiectof thepresen't invention is yLto fprovidefspecial mozzles which may Yloeilocated l at strategic points in afplane for extinguishment {descripticnf-"certain embodiments f my inven- 'ition illustrated 1in *the Vfaxscompanying drawings, iin 4wliich "Figure f1 iseaside'elevation, partly broken `away vands'howniri section, 'of' anairplaneimotorcshow- `Ling :an arrangement'of' theimproved'nozzlein reilation'tothe'cylinders :1ziClaim. (015295-141) ...2 'oneform of "the improvedxnozzle that may be Ausedhaccorc'ling tofffmy invention for'extinguishng Ifaircraft fires.

FFigures 13 :and 14 are 'vertical sections 'of this nozzle, takenonithelines-.-'S and 4-4,respec 1 tively, vof 'Figurel Figure .Bfis aside elevation, partly in section, 'fofa furtherembodiment -of my invention showvingarxother fformliof theI-irrncnovedinozzle `as :aplo "plied Afto -an airplane motor Thaving Ja `single :row

- ofeylinders, and

HFigure '6 isf a'plan view onffa largescalerof one :of vitl-1el nozzles zused 1 in f the .motor f shown in 'Figuref5. l5 i'llurninglnowto V'the drawings, the improved nozzlerislillustrated5in Figure 1 as employedlin fconnectionrwithfone of lthe motors vofan airpl-ane. 'By 1 reference r to applicants :parent ca-se, fnowllPa'tentNo. $2,340,006, theV arrangement ofthe 2o limprovedr nozzle in a :complete iire extinguishing system vwill 4loe more* fully understood. '.Themotor y"illustrated'in l'Eigurel is of the Micylinder radial .'PrattandW'htney TwinfWasp type. Such motors are usually separated into two sections, (i) thefcylinders l3 and the fparts that-must'be located'adj-acent'theretaand (2) the instrument controls, carburetorgoilcooling and pumping sysf1tem,andfthe like iwhich are enclosed'in Aarso- `called 1 auxiliary compartment l I4 disposed lrearfwardly of -1.the'oylinders'l'3 and usually separated therefromby 1a partition such as shownat l5. The cylinders i3 in the forward portion. of `the motor arefusually covered 'by aremovable cowl I'B. "Itis-a'feature'of my invention to provide means 'forextinguishing 'lires in either the forward compartment ofthe'engine encl'rsed-within the cowl '-`|f6-orttheauxliary compartment I`4, or'in -both plaeesf'simultaneously. A"Io this end. I provide-im- 40 vme'diatelyin fron-t io'f the partition |55 and'surroundingthefcrankcase'of the motor as closely laspos`s'il:lle,fa-distritn#ting-'pipe 't8 with a plurality of 4nozzles`2il Aand 2` I extending forwardly from f the l:distributor'pipe it! 8fto points :adacent the base of thecylinders I3. lIf desired the distributor r'piwcefmay bev-.weldedlto or castl as an integralpart y'of thev crankease ofl thefmotor.

In an air-cooled motor yprovided with a doulle -'row offoylinders I3,'such 'as shown'in Figure 1, the cylinders-areusuallystaggered andA separated from each'otherbyfcurved'baiiie plates |9to direct the air around i the cylinders more eiiiciently. 'In such a-motor, the nozzles may consist ofthe '-'short nozzles Vv-which extend to points just back o5 of lthe seconol row of "cylinders and adjacent the 3 bases thereof with the nozzles directed radially outward, and the longer nozzles 2l which extend between each pair of the baille plates I9 to points just back of the centers of the front row of cylinders and near the bases thereof.

In order to extinguish a re in the auxiliary compartment I4, a second distributor pipe 22 of circular or other suitable shape may be installed just back of the partition I5.

The distributor pipe 22 may be connected by a pipe 24 extending rearwardly from the motor and through the interior of the wing in which the motor is mounted to a bottle or other container for the re extinguishing uid, preferably located in the pilots cabin or at some other convenient place in the fuselage of the plane. A short connecting pipe 24a may be used to join the two distributor pipes I8 and 22 for simultaneous operation of the nozzles 20, 2l and 23.

A particularly satisfactory nozzle for use in accordance with my invention is illustrated in Figures 2, 3 and 4, and consists of a tube 32 fitted with a cap 33 fixed in position on its end in any suitable manner as by threads, welding or other suitable means. A semi-circular transverse slit 34 is cut through the pipe 32 and the side of the cap 33 at a point some distance from the forward end of the cap 33 and extending in a plane at a right angle to the tube 32. The forward end of the cap 33 is provided with an internal bore 35 of substantially smaller diameter than the bore of the pipe 32, and another semi-circular transverse slit or opening 36 is cut in the forward end of the cap in an inclined plane as seen in Figs. 2 and 3. The slits or openings 34 and 36 extend only part way around the cap 33 and both may be made of substantially semi-circular shape extending around the same 180 of the surface of the cap 33. It will be apparent, of course, that the slits 34 and 3B do not have to be exactly semi-circular but may extend more or less than 180 around the surface of the cap 33.

The nozzles and 2| are preferably of the construction shown in Figure 2 and are arranged to throw sprays of the re extinguishing fluid radially outward from points just back of and near the bases of the motor cylinders. This spray of extinguisher fluid consists of sheets of the fluid thrown from the outside periphery of the nozzle at a slight angle in a forward direction through the slits 3B and sheets of the fluid thrown from the outside periphery of the nozzle at a, somewhat higher velocity, because of the lower friction loss, through the rear slits 34 in a direction at right angles to air stream flowing around the motor cylinders. These double fluid sheets are subject to the effect of the rapidly moving air stream which tends to bend backward the forwardly inclined sheets of fluid from the slits 36. The two sheets of uid from each nozzle thus serve to reinforce each other and provide a much greater effective radius from the nozzle. In this manner, the nozzles operated simultaneously are capable of throwing outwardly from the crankcase of the motor a curtain of extinguisher iluid for a considerable distance.

By placing the nozzles 20 and 2| just in back of the bases of the motor cylinders I3, the flame from any burning oil or gasoline coming around or over the cylinders or from a crack in the side wall thereof is quickly extinguished. Since the air stream is moving towards the rear of the cylinders, it has been found that the high temperature combustion takes place near the rear edge of the cylinders. A surprising feature of my invention is that the location of the nozzles to deliver extinguisher fluid to the rear portions of the cylinders is far more eiective than placing these nozzles near the front portions of the cylinders. In a high velocity air stream, the extinguisher fluid is dissipated or dispersed too much to be effective if the nozzles are placed too far forward, but the delivery of concentrated sheets of fluid to the rear portions of the cylinders cuts oif the flame quickly and completely without any back ash and without requiring the use of large quantities of fluid.

The re extinguishing system described works most eciently with a suitable halogenated hydrocarbon as thedre extinguishing uid. Carbon tetrachloride is readily available in large quantities and provides an excellent re extinguishing medium. Containers may be partially lled with this liquid and pumped up to a suitable pressure. This pressure should be sufficient to allow all or most of the liquid to be expelled through the nozzles before the pressure is completely lost.

For example, it has been found that with a re extinguishing system using 14 double nozzles of the type shown in Figures 2 to 4, and located around the motor cylinders as shown in Figure l, a gallon or even less carbon tetrachloridefheld in the container-under a pressure of lbs. per square inch is adequate to extinguish any type of nre that may occur in or around the motor cylinders under conditions such as exist during flight of the plane. After the discharge of a gallon of the liquid, the pressure in the container will have dropped to about 40 lbs. per square inch, rbut 'such a pressure is still suicient to produce the full radius of liquid expelled through the nozzles.

Lower initial pressures in the containers may be employed, particularly if smaller quantities o1" extinguisher fluid are used. It will be understood that the exact volume of fluid and the initial pressure needed will depend upon a number cf factors including the number of nozzles, their size, the size of the distributing pipes, etc. Other yhalogenated hydrocarbons, such as methyl bromide or trichlorethylene, or other volatile halogenated hydrocarbons having flre extinguishing properties, or combinations of such halogenated hydrocarbons may be used instead of carbon tetrachloride, as will be understood by those skilled in the art.

Referring now to Figures 5 and 6 which show an arrangement particularly adapted for supplying extinguisher fluid to an air-cooled radial motor having a single row of cylinders, no specific arrangement for supplying extinguisher fluid to the auxiliary compartment is shown, it .being understood that any suitable form such as those previously described or other suitable arrangements of nozzles may be used. In this case, the motor cylinders 5I are surrounded by a suitable cowling52 and are provided around and preferably as close as possible to the crankcase of the motor with a circular distributing pipe 53 which receives extinguisher fluid under pressure from a suitable container through the pipe 54. Nozzles 55 project forwardly from the distributor ring 53 and lie against or close to the crankcase between the motor cylinders 5I.

Nozzles that may be employed for this embodiment are illustrated in more detail in Figure 6, and are provided with two semi-circular` slits 56 and 51 similar to the slits 36 and 34, respectively,

in the nozzles shown in Figure 2. These slits are capable of projecting approximately semi-circular discs or sheets of lire extinguisher iiuid supplied to the slits through the central opening 58 in the main tube 59 of the nozzle. The slit 56 is preferably inclined somewhat to the plane of the slit l in a manner similar to the inclination of the slit 36 in the nozzle shown in Figure 4. Between the slits 55 and 51 is a further slit 60 made by two intersecting cuts at approximately right angles to each other in the tubular head 59a of the nozzle, thus providing an X-shaped opening through which extinguisher uid may be projected. The slits 56, 60 and 5l are all designed to project the extinguisher fluid in the same general direction, and the nozzles 55 are preferably disposed so as to project this uid in a general direction radially outward from the crankcase of the motor.

The nozzles are preferably arranged so that the cross-shaped slits 60 are disposed approximately on the center line of the motor cylinders 5l with the inclined slits 56 ldisposed a substantial distance ahead of the center line of the cylinders. With this arrangement the nozzles 55 in extinguishing a fire project a triple curtain of extinguisher fluid radially outward from points between the motor cylinders and near the bases thereof. The force of the wind stream tends to sweep this curtain of extinguisher fluid rearwardly, so that the iluid from two adjacent nozzles 55 strikes the motor cylinder between them along its rear edge, thus eiectively cutting off any llame streaming from the back of the cylinder.

While the nozzles illustrated in Figures 2, 3, 4 and 6 are particularly eiective in a system as shown and .described herein, it will be apparent 6 to those skilled in the art that such nozzles may also be used eiectively for other purposes.

The terms and expressions which I have employed are used as terms of description and not oi limitation, and I have no intention, in the use of such terms and expressions, of excluding any equivalents of the features shown and described or portions thereof, but recognize that various modifications are possible within the scope of the invention claimed.

I claim:

A nozzle for projecting jets of fluid comprising a tubular member having separate spaced transverse slits therein for projecting jets of fluid, and intersecting slits therebetween for projecting an additional jet of fluid.

PETER GRAHAM MACGREGOR.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 889,972 Schmidt June 9, 1908 1,246,355 Thomas NOV. 13, 1917 1,308,613 Anderson July 1, 1919 1,335,267 Ambrose .Mar. 30, 1920 1,720,145 OConnor July 9, 1929 1,783,237 Greer Dec. 2, 1930 1,814,020 Armstrong July 14, 1931 2,159,219 Madden May 23, 1939 FOREIGN PATENTS Number Country Date 7,185 Great Britain Mar. 26, 1913 450,470 Germany Oct. 8, 1927 

